The fascinating chemistry, biology, and math of hops and beer – more the territory of “mad chemist”

Chemistry and biology of beer

With IPA as the leading craft beer style in America, even casual craft beer drinkers are aware that hops provide the bitter flavor in their favorite beers. But the way that hops are selected and their flavors and aromas are extracted is less well-known – more the territory of “mad chemist” brewers, who must draw on a knowledge of biology, chemistry and math to craft the next big thing. In fact, the ever-evolving chemistry between hops and beer is one of the most fascinating and intricate aspects of the craft beer universe. Here's an in-depth look at everything you need to know about hops as well as how four popular hop varietals affect the flavor, aroma and other characteristics of beer. Hops are the cone-shaped female flower of the vine-like plant humulus lupulus, and the important ingredients are concentrated in the cone’s lupulin glands. Hops are harvested, then dried and processed into pellets, plugs, extracts, or left in their cone form. Those early hop heads knew hops made beer awesome, but thanks to science, we have a better understanding of why.

Four basic ingredients barley, hops, yeast and water, hops. photo from pFriem Family Brewers​

There are two general categories of hops: bittering hops, which have a higher alpha acid content and contribute more bitterness but tend to impart a less refined flavor and aroma; and aroma hops, which are lower in alpha acids, but contribute desirable flavor and aroma characteristics. Some hops are dual-purpose. Read more of this very interesting article including some in depth chemistry of hops discussion. from Beer Connoisseur